What is the formula for calculating plasma O2 content according to Henry's Law?

The formula for calculating plasma oxygen content according to Henry's Law is indeed based on the solubility of oxygen in plasma, which is represented by the constant 0.003. According to Henry’s Law, the amount of a gas that dissolves in a liquid at a given temperature is directly proportional to the partial pressure of that gas above the liquid.

In this context, the formula indicates that for every millimeter of mercury (mmHg) of oxygen partial pressure (PaO2), 0.003 milliliters of oxygen can dissolve in 100 milliliters of plasma. This is crucial for understanding how oxygen is transported in the blood, particularly for patients with respiratory disorders. The other options present different constants, which do not accurately reflect the solubility of oxygen in plasma as per established physiological standards. Therefore, the correct formulation highlights the role of PaO2 in determining the dissolved oxygen content in the blood plasma.